1. Field of the Invention
The present invention relates generally to medical instruments and, more specifically, to apparatus and methods for suturing tissue. The apparatus and methods are particularly useful for the repair of tissue lacerations in closed spaces such as meniscal lacerations in the knee, and the like.
A variety of injuries and diseases, including many which previously required surgery, may be diagnosed and treated through scope-type medical instruments. Fiber optic arthroscopes are representative of these devices. Using an arthroscope, a physician may confirm the presence of lesions detected by other diagnostic methods as well as reveal lesions that have been missed. A physician may also repair some lesions through an arthroscope.
Since arthroscopes are introduced through relatively small surgical incisions, arthroscopic procedures are less invasive than open surgical procedures. Because arthroscopic procedures are less invasive, they are less costly and are associated with less morbidity than open procedures. Arthroscopic procedures are often done on an outpatient basis.
In addition to the diagnostic value of arthroscopic procedures, a variety of therapeutic procedures may be performed through an arthroscope. For example, meniscectomy (surgical removal of a meniscus in the knee) may be performed through an arthroscope.
Although meniscectomy is performed on meniscal injuries, meniscal repair is advisable for many meniscal injuries, e.g., vascular zone lacerations. Hanks et al., Orthopaedic Review, 19(6):541-548 (1990). Meniscal repair requires approximation and fixation of the edges of the meniscal laceration with sutures. When repaired arthroscopically, suturing the meniscal laceration must be done in a small closed space.
Several techniques have been developed to place sutures in the meniscus during arthroscopic repair. In one technique, a double cannula is placed within the knee joint. Two 10 inch needles with suture attached are directed to the meniscal body at the site of the laceration through the double cannula. The needles are pushed through the meniscus and retrieved in an incision on the opposite side of the meniscus. The suture is knotted at the point where the needles exit the joint.
In an alternative method of arthroscopically suturing meniscal tears, a large bore needle is passed from an incision outside the knee joint through the meniscal tear and body. The suture is placed through the needle into the joint. The end of the suture is brought out of the joint with an arthroscope and knotted. The needle is withdrawn, the suture pulled back into the joint and abutted into the meniscal body. Another suture is similarly placed in close proximity to the first. The two sutures are tied in the incision through which the needle passed.
Even with the availability of the above instruments, tissue repair and suture placement are difficult and time consuming for many physicians. Thus it is desirable to provide improved apparatus and methods for placing sutures in a remote and confined space. The apparatus should be able to reach the target location while requiring minimal work space. Furthermore, the techniques using the apparatus to place sutures should not be cumbersome to perform and should rely on dexterity skills which a surgeon already possesses. The present invention fulfills this and other needs.
2. Description of the Background Art
Many devices in general medical use are employed for suturing in closed spaces. For example, large bore spinal needles have been used as a conduit to transport sutures through meniscal bodies and joint capsules. Hanks et al., supra. Keith needles are also used to place sutures arthroscopically. Barber et al., J. Bone and Joint Surgery, 67-B(1):39-41 (1985). Keith needles are straight needles which are manufactured either with suture attached to the proximal end of the needle or with a permanently closed eye for threading suture.
Other devices have been developed specifically for closed space suture placement through a scope. The Henning needle-holder is specifically adapted for arthroscopically placing sutures. The Henning needle-holder firmly holds needles in such a way as to allow a surgeon to precisely control suture placement.
U.S. Pat. No. 3,871,379 describes instruments for laproscopic suturing. The suture needle is secured to a needle-holder capable of altering the alignment between the needle and needle-holder. The needle has an open protuberance at the distal end to hold the suture.
U.S. Pat. No. 4,641,652 describes a device to endoscopically tie knots in suture. The device does not assist suture placement.
U.S. Pat. No. 4,760,848 describes a rotational surgical instrument which may be used for endoscopically placing sutures. The instrument includes a rotating head comprising a pair of jaws. The jaws may be closed to hold a needle. Rotation of the head allows curved needles to penetrate tissue and place suture.
U.S. Pat. No. 4,923,461 describes a suturing instrument useful in arthroscopic surgery. The instrument, which resembles a conventional grasper and forceps-type microsurgical instrument, includes a hollow tip for engaging tissue to be sutured and a recess for securing a hollow tubular needle through which to pass suture.
The disclosures of each of the foregoing references are incorporated herein by reference.